This invention relates generally to methods and apparatus for electricity metering, and more particularly, to methods and apparatus for defining data calculations in a microcomputer based electricity meter.
Electronic electricity meters for metering multi-phase services typically include a digital signal processor (DSP) and a microcomputer. Certain functions and operations are separately performed in the DSP and microcomputer. By dividing the functionality between the DSP and microcomputer, communications of data and commands must be provided between the DSP and microcomputer. Such an architecture is complex.
In addition, such meters typically are programmed to perform certain functions. Although the meters are upgradeable, the types of upgrades that can be performed are limited to the tables and functions prestored in the meter. In addition, and in the past, increased functionality typically was a trade-off to cost. That is, adding functionality to the meter typically resulted in adding significant costs to the meter.
It would therefore be desirable to provide methods and apparatus to define meter data calculations providing increased functionality and flexibility, preferably at relatively low cost.
There is therefore provided, in one embodiment of the present invention, a method for defining meter data calculations in an electronic electricity meter. The method includes steps of: storing a set of predefined data calculation instructions in a non-volatile memory of the meter; storing a first set of vectors in a memory of the meter, the vectors pointing to data calculations of the set of predefined data calculation instructions; metering a plurality of electrical quantities of a power source; and controlling calculations performed on the metered electrical quantities in accordance with the data calculation instructions pointed to by the first stored set of vectors.
This embodiment and others described provide high functionality and flexibility in defining meter data calculations, and do so at low cost: